Fasten Health
Fasten Health is a healthcare data interoperability company offering a unified medical record platform that gives patients and developers access to clinical data across the U.S. healthcare system. Fasten began as an open-source project — Fasten OnPrem, a self-hosted personal/family electronic medical record manager that ingests FHIR Bundles and is distributed under GPL-3.0 with 2.7k+ GitHub stars. The team then productized the connectivity layer as Fasten Connect, a commercial REST + FHIR API and Stitch client SDK suite that lets developers retrieve clinical records from 50,000+ healthcare systems and 60,000+ organizations including Epic, Cerner, MyChart, Kaiser Permanente, HCA, Ascension, Humana, and Medicare. Founded by engineers who lived through the fragmentation of health data firsthand and based in New York City, Fasten ships GPL/MIT/Apache 2.0 open source repos alongside the hosted Fasten Connect platform.
Solid contracts, transparent operations, and an easy start — typically complete on four or five facets with one clear soft spot.
API Evangelist profiles Fasten Health the way a machine reads it — 19 machine-readable artifacts across 1 API, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.
Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — Fasten Health scores 58.8/100 (strong), with a separate agent-readiness read of 39/100 (agent native). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.
Kin Score
This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance. Every facet and dimension name is a link: it opens that measurement's page on APIs.io, where the rating runs across the whole catalog — the exact checks that feed it, how every profiled provider distributes on it, and who is at the top of it.
Kin Score
How this is scored →scored 2026-09-08 · rubric v0.20.0
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How we profile Fasten Health
Each block below is one kind of artifact we hold for Fasten Health. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.
APIs 11
Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.
Individual APIs this provider publishes, each with its own machine-readable definition.
Fasten OnPrem
Fasten OnPrem is an open-source, self-hosted, personal and family electronic medical record manager written in Go (47%) and TypeScript (35%). It runs as a Docker container behin...
Fasten Connect Webhooks
Fasten Connect emits HMAC-verified webhook events to notify integrators of asynchronous operations such as EHI export completion, connection lifecycle changes, and TEFCA workflo...
Fasten Stitch Client SDKs
Stitch is Fasten Connect's client-side embeddable component that lets a patient pick their healthcare provider, authenticate, and grant data-sharing consent inside a host applic...
Fasten Identity Proofing & TEFCA IAS
Identity proofing endpoints and guides cover Fasten-issued identity verification as well as a Bring Your Own Identity path for integrators that already meet NIST IAL2 / TEFCA IA...
gofhir-models
Apache 2.0 licensed Go client library and generated FHIR resource models used by Fasten's services to parse, validate, and emit FHIR R4 payloads. Maintained as a standalone open...
fhir-react
MIT-licensed React component library for rendering FHIR resources, useful for building patient portals and clinical viewers on top of Fasten data.
Fasten Toolbox
Standalone FHIR-based developer tools derived from the main Fasten platform, including catalog browsing, display component previews, and other utilities for working with FHIR data.
Folio
Apache 2.0 licensed modern PDF library for Go with a layout engine, HTML-to-PDF conversion, form-fill support, digital signatures, and barcode rendering. Open-sourced by Fasten ...
Fasten Connect Quickstart Sample
MIT-licensed JavaScript starter project that demonstrates an end-to-end Fasten Connect integration — credential setup, Stitch embed, bulk EHI export request, and webhook-driven ...
Fasten Answers AI
GPL-3.0 licensed Python proof-of-concept for AI-powered health insights — exploratory work on conversational querying of a patient's longitudinal medical record using LLMs.
Fasten Health Bridge API
Customer (organization) facing APIs
Scroll within the panel for all 11 ·
Pricing Plans 1
Pricing is part of the interface. Machine-readable plans tell you what a tier costs and includes before you commit — one of the things the Kin Score reads for access clarity — renamed from commercial clarity in rubric 0.12, because a free statutory interface has access terms and no commercial ones.
Published pricing tiers and plan structures.
Rate Limits 1
Rate limits are the difference between a demo that works and a production integration that doesn't fall over. Publishing them is an operational-transparency signal — and a hard requirement for any agent that plans its own throughput.
Documented rate limits and quota policies.
Fasten Health Rate Limits
RATE LIMITSEvent Specifications 1
Not every API is request/response. AsyncAPI describes the event-driven and streaming side — the webhooks and channels — so the asynchronous half of the interface is documented the same way the synchronous half is.
AsyncAPI definitions for this provider's event-driven and streaming APIs.
Fasten Health Webhooks
ASYNCAPISecurity Posture 3
Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Scopes 1
OAuth scopes are the vocabulary of least-privilege access. Profiling them shows exactly what an integration — or an agent acting on a user's behalf — is allowed to do.
OAuth scopes governing access to this provider's APIs.
Agentic Access 1
An x-agentic-access contract marks which operations are safe for an agent to run on its own and which need a human in the loop. It is the difference between an API an agent can use and one it can use safely.
Recommended x-agentic-access execution contracts for AI agents.
Resources
Every other property we hold for Fasten Health — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.
Get Started 7
Portal, sign-up, and the first successful call
Scroll within the panel for all 7 ·
Documentation 3
Reference material describing how the API behaves
Agent Surfaces 4
MCP servers, agent skills, and machine-readable catalogs
Design & Contract 8
Pagination, idempotency, versioning, errors, and events
Scroll within the panel for all 8 ·
Build 6
SDKs, sample code, and the tooling you integrate with
Access & Security 5
Authentication, authorization, and security posture
Operate 7
Status, limits, changes, and where to get help
Scroll within the panel for all 7 ·
Commercial 5
Pricing, plans, and the legal terms of use
Company 3
The organization behind the API
Other 4
Properties that don't map to a standard resource type
← All providers · Data indexed from github.com/api-evangelist/fasten-health · machine-readable index on apis.io
This is an independent, third-party profile of Fasten Health, published by API Evangelist. We do not operate, host, resell, or support these APIs, and we are not affiliated with or endorsed by the company unless stated above. Everything here is built from publicly available information — the company's own site, developer portal, documentation, public repositories, and the specifications it publishes for public use. Nothing is obtained by breaching a system, defeating an access control, or using credentials.
The Kin Score and Agent Readiness rating are independently calculated assessments of a company's public API artifacts, scored against a published rubric. They are not certifications, endorsements, security assessments, or audits.
Corrections, re-scores, and removal are free — no partnership or purchase required, and you do not need to justify the request. A removed company is recorded as unrated, never scored zero for having asked. Acknowledgement within one business day; removal within two.
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